Efficient light extraction and beam shaping from flexible, optically integrated organic light-emitting diodes

Efficient out-coupling light extraction and optical beam shaping have been combined to form an integrated, flexible illuminator that is based on organic light-emitting diodes (OLEDs). Spherical refractive microlenses were replicated by a cost-effective UV-casting technique onto a plastic foil to achieve the customized Gaussian distribution of the electroluminescence of an OLED pixel (50 mu m) matrix. The fabricated optical device, namely a ceiling light illuminator, shows an improvement of 70% in the out-coupled emission measured in the far field. The result corresponds to the theoretical prediction for isotropic emitting sources. (c) 2006 American Institute of Physics.